Problem: $ { \left[\begin{array}{rr}{1} & {0} \\ {1} & {3} \\ {4} & {2}\end{array}\right]+\left[\begin{array}{rr}{0} & {-2} \\ {0} & {2} \\ {4} & {2}\end{array}\right] = {?} } $
To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{1}+{0} & {0}+{-2} \\ {1}+{0} & {3}+{2} \\ {4}+{4} & {2}+{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{1} & {-2} \\ {1} & {5} \\ {8} & {4}\end{array}\right]}$